Refactor SAR marker handling and add template management

- Updated CompassSarList and DetailedCompassDialog to use marker.displayName instead of marker.type.displayName.
- Enhanced DrawingLayer and DrawingMarkersLayer to support simple mode for drawing visibility and interaction.
- Added toggle switches in DrawingToolbar for showing/hiding received drawings and SAR markers.
- Modified MapMarkers to utilize custom emojis and display names for markers.
- Introduced RecipientSelectorSheet for selecting message recipients with search functionality.
- Refactored SarUpdateSheet to use SAR templates instead of marker types, allowing for emoji and name customization.
- Created SarTemplateEditDialog for adding and editing SAR templates with color selection and preview.

lib/widgets/map/compass/compass_sar_list.dart

@@ -124,7 +124,7 @@ class CompassSarList extends StatelessWidget {
                 color: markerColor,
                 size: 24,
               ),
-              title: Text(marker.type.displayName),
+              title: Text(marker.displayName),
               subtitle: Text(
                 '${_bearingToCardinal(bearing)} • ${_formatDistance(distance)} • ${marker.timeAgo}',
                 style: Theme.of(context).textTheme.bodySmall,